It has been shown from the results of many epidemiological surveys that the concentration of serum lipoprotein is related to diseases such as dyslipidemia and arteriosclerosis (for example, Badimon, J. Clin. Invest., 1990, Vol. 85, pp. 1234-1241). Both an increase in the blood concentration of low density lipoprotein (hereinafter, referred to as LDL) cholesterol and a decrease in the blood concentration of high density lipoprotein (hereinafter, referred to as HDL) cholesterol are risk factors for coronary disease.
Cholesterol in the peripheral tissue is extracted by HDL and esterified in HDL to become cholesteryl ester (hereinafter, referred to as CE). Cholesteryl ester transfer protein (hereinafter, referred to as CETP) transfers the CE in HDL to LDL. Therefore, inhibition of CETP action increases the concentration of the CE in HDL and decreases the concentration of the CE in LDL. As described above, it is considered that a medicine which inhibits CETP activity is useful as a medicament for treatment or prophylaxis of diseases such as dyslipidemia and arteriosclerosis (for example, N. Engl. J. Med., 2004, Vol. 350, pp. 1505-1515).
Certain pyridine compounds that have CETP inhibition activity are known (for example, see Patent references 1 to 8). In addition, certain pyrimidinyl piperidine compounds that have CETP inhibition activity are known (for example, see Patent references 9 to 13).